U.S. patent number 10,798,647 [Application Number 16/379,170] was granted by the patent office on 2020-10-06 for network slice selection.
This patent grant is currently assigned to Apple Inc.. The grantee listed for this patent is Apple Inc.. Invention is credited to Haijing Hu, Huarui Liang, Haining Wang, Dawei Zhang.
United States Patent |
10,798,647 |
Wang , et al. |
October 6, 2020 |
Network slice selection
Abstract
This disclosure relates to techniques for network slice
selection. A network slice selection function of a cellular network
may receive a network slice selection request from a radio access
network node of the cellular network. The network slice selection
request may be received by the radio access network node from a
wireless device. A core network slice (and possibly a radio access
network slice) of the cellular network may be selected for the
service request. A network slice selection response may be provided
to the radio access network node, indicating a control plane entry
point address for the selected core network slice. The selected
radio network slice may also be indicated in the network slice
selection response.
Inventors: |
Wang; Haining (Beijing,
CN), Liang; Huarui (Beijing, CN), Hu;
Haijing (Beijing, CN), Zhang; Dawei (Saratoga,
CA) |
Applicant: |
Name |
City |
State |
Country |
Type |
Apple Inc. |
Cupertino |
CA |
US |
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Assignee: |
Apple Inc. (Cupertino,
CA)
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Family
ID: |
1000005100137 |
Appl.
No.: |
16/379,170 |
Filed: |
April 9, 2019 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20190239156 A1 |
Aug 1, 2019 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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15128622 |
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10278123 |
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PCT/CN2016/088320 |
Jul 4, 2016 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04W
48/18 (20130101); H04W 48/10 (20130101); H04W
48/12 (20130101); H04W 8/20 (20130101); H04W
76/11 (20180201); H04W 48/16 (20130101); H04W
76/12 (20180201); H04W 16/24 (20130101) |
Current International
Class: |
H04B
7/00 (20060101); H04W 76/11 (20180101); H04W
8/20 (20090101); H04W 76/12 (20180101); H04W
48/12 (20090101); H04W 48/10 (20090101); H04W
48/18 (20090101); H04W 48/16 (20090101); H04W
16/24 (20090101) |
Field of
Search: |
;370/310,328,338,341,349,465 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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103650437 |
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Mar 2014 |
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CN |
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105516312 |
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Apr 2016 |
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CN |
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A 2013-537725 |
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Oct 2013 |
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JP |
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WO 2017/097169 |
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Jun 2017 |
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WO |
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WO 2017/173404 |
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Oct 2017 |
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WO |
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Other References
Hu, et al., "A Joint Utility Optimization Based Virtual AP and
Network Slice Selection Scheme for SDWNs"; 2015 10th International
Conference on Communications and Networking in China (China Com);
Aug. 15-17, 2015; 6 pages. cited by applicant .
Shimojo et al.; "Future Core Network for the 5G Era"; NTT Docomo
Technical Journal; No. 4, vol. 17; Apr. 30, 2016. cited by
applicant .
International Search Report and Written Opinion, Application No.
PCT/CN2016/088320, dated Apr. 7, 2017, 11 pages. cited by applicant
.
Huawei et al.; "UE Slice Association/Overload Control Procedure";
3GPP TSG SA WG2 Meeting #115, S2-163161; May 23-27, 2016; Nanjing,
China; pp. 1-9. cited by applicant .
3GPP TR 23.799 V0.5.0 (May 2016) ; Technical Report; 3rd Generation
Partnership Project; Technical Specification Group Services and
System Aspects; Study on Architecture for Next Generation System
(Release 14), May 2016; 179 pages. cited by applicant .
CATT; "Network slicing architecture and slice selection mechanism":
SA WG2 Meeting #115, S2-162652; May 23-27, 2016; Nanjing, China; 3
pages. cited by applicant .
6G Electronics; "Initial network slice instance selection (update
of solution 1.3)"; SA WG2 Meeting #115 S2-162627; May 23-27, 2016;
Nanjing, China; 3 pages. cited by applicant .
Examination report No. 1 for standard patent application,
Australian Application No. 2016379814, dated May 31, 2018, 6 pages.
cited by applicant .
ZTE; "Consideration on RAN architecture impacts of network
slicing"; 3GPP TSG-RAN WG2#93bis; Apr. 15, 2016; R2-162627; eight
pages. cited by applicant .
Office Action, Japanese Patent Application No. 2017-533848, dated
Sep. 18, 2018, six pages. cited by applicant .
Examination report No. 2 for standard patent application,
Australian Application No. 2016379814, dated Sep. 24, 2018, five
pages. cited by applicant .
Examination Report No. 4, Application No. 2016379814, dated Jan.
15, 2019, 5 pages. cited by applicant .
Nokia, Alcatel-Lucent Shanghai Bell, "RAN Selection of CN Entity
based on Network Slicing," 3GPP TSG-RAN WG3 #92, 3GPP, May 27,
2016, R3-161357, four pages. cited by applicant .
China Mobile, Sprint, NEC, CATT, CATR, Deutsche Telekom, Ericsson,
"Network Slicing Architecture and High-Level Function Definition,"
3GPP TSG-SA WG2 #115, 3GPP, May 27, 2016, S2-162365, seven pages.
cited by applicant .
Office Action, Japanese Patent Application No. 2019-019897, dated
Dec. 6, 2019, three pages. cited by applicant.
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Primary Examiner: Levitan; Dmitry
Attorney, Agent or Firm: Kowert, Hood, Munyon, Rankin &
Goetzel, P.C.
Parent Case Text
PRIORITY CLAIM
This application is a continuation of and claims priority to U.S.
patent application Ser. No. 15/128,622, entitled "Network Slice
Selection," filed Sep. 23, 2016, which is the U.S. National Stage
Application of International Patent Application No.
PCT/CN2016/088320, titled "Network Slice Selection", filed Jul. 4,
2016, each of which is hereby incorporated by reference in its
entirety as though fully and completely set forth herein.
The claims in the instant application are different than those of
the parent application or other related applications. The Applicant
therefore rescinds any disclaimer of claim scope made in the parent
application or any predecessor application in relation to the
instant application. The Examiner is therefore advised that any
such previous disclaimer and the cited references that it was made
to avoid, may need to be revisited. Further, any disclaimer made in
the instant application should not be read into or against the
parent application or other related applications.
Claims
What is claimed is:
1. An apparatus, comprising: a memory; and a processor operably
coupled to the memory and configured to cause a network slice
selection function (NSSF) of a cellular network to: receive a
network slice selection request associated with a non-access
stratum (NAS) request by a user equipment device (UE), wherein the
network slice selection request comprises a network slice
identifier (NSID) indicating a UE-preferred network slice for the
UE included in the NAS request; select a network slice based on at
least a network operator's policy, wherein to select the network
slice the processor is configured to cause the NSSF to: determine
that the UE-preferred network slice is not compatible with a
selection policy; and select a network slice of the cellular
network different from the UE-preferred network slice in response
to the network slice selection request, wherein the selected
network slice matches the selection policy; and provide a network
slice selection response, wherein the network slice selection
response indicates the selected network slice, wherein the selected
network slice is associated with a control plane entry point.
2. The apparatus of claim 1, wherein the network slice selection
response includes an address for the associated control plane entry
point.
3. The apparatus of claim 1, wherein selecting the network slice is
further based at least in part on information received from the UE
by way of the network slice selection request and NAS request.
4. The apparatus of claim 1, wherein the processor is further
configured to cause the NSSF to: request user subscription
information for the UE from a user subscription information
repository of the cellular network; and receive user subscription
information for the UE from the user subscription information
repository, wherein selecting the network slice is based at least
in part on the user subscription information received from the user
subscription information repository.
5. The apparatus of claim 4, wherein the processor is further
configured to cause the NSSF to: store the user subscription
information for the UE for at least a period of time in which the
stored user subscription information is considered valid; and
perform network slice selections for the UE during the period of
time in which the stored user subscription information is
considered valid based at least in part on the stored user
subscription information.
6. The apparatus of claim 1, wherein the network slice selection
request is received from a radio access network (RAN) node of the
cellular network, wherein the network slice selection response is
provided to the RAN node of the cellular network, wherein the NSSF
does not process user plane data for the UE.
7. The apparatus of claim 1, wherein the network slice selection
response further indicates a selected set of control plane network
functions associated with the selected network slice.
8. The apparatus of claim 1, wherein the selected network slice
comprises a radio access network (RAN) slice and a core network
(CN) slice.
9. A non-transitory memory medium, comprising program instructions,
wherein the program instructions are executable by a processing
element and cause, when executed by the processing element, a
network slice selection function (NSSF) of a cellular network to:
receive a network slice selection request associated with a
non-access stratum (NAS) request received by a radio access network
(RAN) node from a user equipment device (UE), wherein the network
slice selection request comprises a network slice identifier (NSID)
indicating a UE-preferred network slice for the UE included in the
NAS request; select a network slice based on at least a network
operator's policy, wherein to select the network slice the
processing element is configured to cause the NSSF to: determine
that the UE-preferred network slice is not compatible with a
selection policy; and select a network slice of the cellular
network different from the UE-preferred network slice in response
to the network slice selection request, wherein the selected
network slice matches the selection policy; and provide a network
slice selection response, wherein the network slice selection
response indicates the selected network slice, wherein the selected
network slice is associated with a control plane entry point.
10. The non-transitory memory medium of claim 9, wherein the
network slice selection request comprises, for the NAS request, an
indication of one or more of: UE identification information;
service type information; or application identification
information.
11. The non-transitory memory medium of claim 9, wherein the
program instructions are further executable to cause the NSSF to:
determine whether valid subscription information for the UE is
stored by the NSSF; and obtain subscription information for the UE
from a home subscriber server (HSS) of the cellular network if
valid subscription information for the UE is not stored by the
NSSF, wherein the network slice selection response indicates the
control plane entry point for the network slice based at least in
part on the subscription information for the UE.
12. The non-transitory memory medium of claim 9, wherein the
selected network slice is also selected by the NSSF when the NAS
request does not include a UE-preferred network slice.
13. The non-transitory memory medium of claim 9, wherein the
program instructions are further executable to cause the NSSF to:
select a core network slice of the cellular network for the NAS
request in response to the network slice selection request; and
select a RAN slice of the cellular network for the NAS request in
response to the network slice selection request, wherein the
network slice selection response further indicates that the core
network slice and the RAN slice are selected for the NAS
request.
14. A method for managing a network slice selection function (NSSF)
of a cellular network, the method comprising: at the NSSF:
receiving a network slice selection request associated with a
non-access stratum (NAS) request by a user equipment device (UE),
wherein the network slice selection request comprises a network
slice identifier (NSID) indicating a UE-preferred network slice for
the UE; selecting a network slice based on at least a network
operator's policy, wherein selecting the network slice includes:
determining that the UE-preferred network slice is not compatible
with a selection policy; and selecting a network slice of the
cellular network different from the UE-preferred network slice in
response to the network slice selection request, wherein the
selected network slice matches the selection policy; and providing
a network slice selection response, wherein the network slice
selection response indicates the selected network slice, wherein
the selected network slice is associated with a control plane entry
point.
15. The method of claim 14, wherein selecting the network slice is
based at least in part on information received from the UE by way
of the NAS request.
16. The method of claim 14, the method further comprising:
requesting user subscription information for the UE from a user
subscription information repository of the cellular network; and
receiving user subscription information for the UE from the user
subscription information repository, wherein the selected network
slice is selected based at least in part on the user subscription
information received from the user subscription information
repository.
17. The method of claim 16, the method further comprising: storing
the user subscription information for the UE for at least a period
of time in which the stored user subscription information is
considered valid; and performing network slice selections for the
UE during the period of time in which the stored user subscription
information is considered valid based at least in part on the
stored user subscription information.
18. The method of claim 14, wherein the network slice selection
response further indicates a selected set of control plane network
functions associated with the selected network slice.
19. The method of claim 14, wherein the selected network slice
comprises a radio access network (RAN) slice and a core network
(CN) slice.
20. The method of claim 14, the method comprising: receiving a
second network slice selection request associated with a second NAS
request by a second UE, wherein the second NAS request does not
include a UE-preferred network slice, wherein the selected network
slice is also selected for the second UE in response to the second
NAS request.
Description
FIELD
The present application relates to apparatuses, systems, and
methods for network slice selection.
DESCRIPTION OF THE RELATED ART
Wireless communication systems are rapidly growing in usage.
Further, wireless communication technology has evolved from
voice-only communications to also include the transmission of data,
such as Internet and multimedia content. Some examples of wireless
communication standards include GSM, UMTS (associated with, for
example, WCDMA or TD-SCDMA air interfaces), LTE, LTE Advanced
(LTE-A), HSPA, 3GPP2 CDMA2000 (e.g., 1.times.RTT, 1.times.EV-DO,
HRPD, eHRPD), IEEE 802.11 (WLAN or Wi-Fi), IEEE 802.16 (WiMAX),
Bluetooth, and others.
As demand for wireless communication systems grows and new use
cases for wireless communication arise, there is a seemingly
continual need to develop next generation wireless communication
techniques and standards. One such developing concept may include
network slicing, which may allow a network operator to create
different "network slices" configured to address different wireless
communication use cases and scenarios in a customized manner.
SUMMARY
Techniques for a cellular network to determine or select which
network slice, and which network slice functions within a network
slice, are to be used for a given service request by a wireless
device attached to the cellular network, may be important in order
to effectively support network slicing by network operators.
Embodiments are presented herein of apparatuses, systems, and
methods for performing network slice selection.
According to the techniques described herein, a network
architecture may be proposed in which a network slice selection
entity of a cellular network is provided with an interface to a
radio access network node of the cellular network and an interface
to a user data repository of the cellular network. The network
slice selection entity may be responsible for selecting a network
slice (potentially including a core network slice and/or a radio
access network slice) for a particular wireless device connection,
e.g., upon request by the serving radio access network node for the
wireless device. The network slice selection may be based on a
service type and/or application associated with the service request
for which network slice selection is being performed, user
subscription information, network operator policy, and/or any of
various other considerations. In some instances, the wireless
device may provide an indication of a preferred network slice for
its service request, which may be considered by the network slice
selection entity when selecting the network slice.
The network slice selection entity may not itself perform control
signal or user data routing, but may store address information for
the control plane entry point for each core network slice, and may
provide that information to a radio access network node that
requests network slice selection in response to the request.
Further according to the techniques described herein, it may be
possible for a wireless device to connect to multiple network
slices at the same time. For example, each service or connection
request may trigger a new query to the network slice selection
entity, which may result in some or all of those service or
connection request being associated with different network
slices.
The techniques described herein may be implemented in and/or used
with a number of different types of devices, including but not
limited to cellular phones, tablet computers, wearable computing
devices, portable media players, cellular base stations and other
cellular network infrastructure equipment, servers, and any of
various other computing devices.
This summary is intended to provide a brief overview of some of the
subject matter described in this document. Accordingly, it will be
appreciated that the above-described features are merely examples
and should not be construed to narrow the scope or spirit of the
subject matter described herein in any way. Other features,
aspects, and advantages of the subject matter described herein will
become apparent from the following Detailed Description, Figures,
and Claims.
BRIEF DESCRIPTION OF THE DRAWINGS
A better understanding of the present subject matter can be
obtained when the following detailed description of the embodiments
is considered in conjunction with the following drawings, in
which:
FIG. 1 illustrates an exemplary (and simplified) wireless
communication system;
FIG. 2 illustrates an exemplary base station (BS) in communication
with an exemplary wireless user equipment (UE) device, according to
some embodiments;
FIG. 3 illustrates an exemplary block diagram of a UE device,
according to some embodiments;
FIG. 4 illustrates an exemplary block diagram of a BS, according to
some embodiments;
FIG. 5 illustrates an exemplary block diagram of a core network
element, according to some embodiments;
FIG. 6 illustrates a first exemplary possible network slice
selection logical architecture, according to some embodiments;
FIG. 7 illustrates a second exemplary possible network slice
selection logical architecture, according to some embodiments;
FIGS. 8-9 illustrate a third exemplary possible network slice
selection logical architecture and associated procedures signal
flow, according to some embodiments;
FIGS. 10-11 illustrate a fourth exemplary possible network slice
selection logical architecture and associated procedures signal
flow, according to some embodiments; and
FIGS. 12-13 illustrate a proposed exemplary possible network slice
selection logical architecture and associated procedures signal
flow, according to some embodiments.
While the features described herein may be susceptible to various
modifications and alternative forms, specific embodiments thereof
are shown by way of example in the drawings and are herein
described in detail. It should be understood, however, that the
drawings and detailed description thereto are not intended to be
limiting to the particular form disclosed, but on the contrary, the
intention is to cover all modifications, equivalents and
alternatives falling within the spirit and scope of the subject
matter as defined by the appended claims.
DETAILED DESCRIPTION
Terms
The following is a glossary of terms used in the present
disclosure:
Memory Medium--Any of various types of non-transitory memory
devices or storage devices. The term "memory medium" is intended to
include an installation medium, e.g., a CD-ROM, floppy disks, or
tape device; a computer system memory or random access memory such
as DRAM, DDR RAM, SRAM, EDO RAM, Rambus RAM, etc.; a non-volatile
memory such as a Flash, magnetic media, e.g., a hard drive, or
optical storage; registers, or other similar types of memory
elements, etc. The memory medium may include other types of
non-transitory memory as well or combinations thereof. In addition,
the memory medium may be located in a first computer system in
which the programs are executed, or may be located in a second
different computer system which connects to the first computer
system over a network, such as the Internet. In the latter
instance, the second computer system may provide program
instructions to the first computer for execution. The term "memory
medium" may include two or more memory mediums which may reside in
different locations, e.g., in different computer systems that are
connected over a network. The memory medium may store program
instructions (e.g., embodied as computer programs) that may be
executed by one or more processors.
Carrier Medium--a memory medium as described above, as well as a
physical transmission medium, such as a bus, network, and/or other
physical transmission medium that conveys signals such as
electrical, electromagnetic, or digital signals.
Programmable Hardware Element--includes various hardware devices
comprising multiple programmable function blocks connected via a
programmable interconnect. Examples include FPGAs (Field
Programmable Gate Arrays), PLDs (Programmable Logic Devices), FPOAs
(Field Programmable Object Arrays), and CPLDs (Complex PLDs). The
programmable function blocks may range from fine grained
(combinatorial logic or look up tables) to coarse grained
(arithmetic logic units or processor cores). A programmable
hardware element may also be referred to as "reconfigurable
logic".
Computer System--any of various types of computing or processing
systems, including a personal computer system (PC), mainframe
computer system, workstation, network appliance, Internet
appliance, personal digital assistant (PDA), television system,
grid computing system, or other device or combinations of devices.
In general, the term "computer system" can be broadly defined to
encompass any device (or combination of devices) having at least
one processor that executes instructions from a memory medium.
User Equipment (UE) (or "UE Device")--any of various types of
computer systems devices which are mobile or portable and which
performs wireless communications. Examples of UE devices include
mobile telephones or smart phones (e.g., iPhone.TM.,
Android.TM.-based phones), portable gaming devices (e.g., Nintendo
DS.TM., PlayStation Portable.TM., Gameboy Advance.TM., iPhone.TM.),
wearable devices (e.g., smart watch, smart glasses), laptops, PDAs,
portable Internet devices, music players, data storage devices, or
other handheld devices, etc. In general, the term "UE" or "UE
device" can be broadly defined to encompass any electronic,
computing, and/or telecommunications device (or combination of
devices) which is easily transported by a user and capable of
wireless communication.
Wireless Device--any of various types of computer system devices
which performs wireless communications. A wireless device can be
portable (or mobile) or may be stationary or fixed at a certain
location. A UE is an example of a wireless device.
Communication Device--any of various types of computer systems or
devices that perform communications, where the communications can
be wired or wireless. A communication device can be portable (or
mobile) or may be stationary or fixed at a certain location. A
wireless device is an example of a communication device. A UE is
another example of a communication device.
Base Station--The term "Base Station" has the full breadth of its
ordinary meaning, and at least includes a wireless communication
station installed at a fixed location and used to communicate as
part of a wireless telephone system or radio system.
Cell--The term "cell" as used herein may refer to an area in which
wireless communication services are provided on a radio frequency
by a cell site or base station. A cell may be identified in various
instances by the frequency on which the cell is deployed, by a
network (e.g., PLMN) to which the cell belongs, and/or a cell
identifier (cell id), among various possibilities.
Link Budget Limited--includes the full breadth of its ordinary
meaning, and at least includes a characteristic of a wireless
device (e.g., a UE) which exhibits limited communication
capabilities, or limited power, relative to a device that is not
link budget limited, or relative to devices for which a radio
access technology (RAT) standard has been developed. A UE that is
link budget limited may experience relatively limited reception
and/or transmission capabilities, which may be due to one or more
factors such as device design, device size, battery size, antenna
size or design, transmit power, receive power, current transmission
medium conditions, and/or other factors. Such devices may be
referred to herein as "link budget limited" (or "link budget
constrained") devices. A device may be inherently link budget
limited due to its size, battery power, and/or transmit/receive
power. For example, a smart watch that is communicating over LTE or
LTE-A with a base station may be inherently link budget limited due
to its reduced transmit/receive power and/or reduced antenna.
Wearable devices, such as smart watches, are generally link budget
limited devices. Alternatively, a device may not be inherently link
budget limited, e.g., may have sufficient size, battery power,
and/or transmit/receive power for normal communications over LTE or
LTE-A, but may be temporarily link budget limited due to current
communication conditions, e.g., a smart phone being at the edge of
a cell, etc. It is noted that the term "link budget limited"
includes or encompasses power limitations, and thus a power limited
device may be considered a link budget limited device.
Processing Element--refers to various elements or combinations of
elements. Processing elements include, for example, circuits such
as an ASIC (Application Specific Integrated Circuit), portions or
circuits of individual processor cores, entire processor cores,
individual processors, programmable hardware devices such as a
field programmable gate array (FPGA), and/or larger portions of
systems that include multiple processors.
Channel--a medium used to convey information from a sender
(transmitter) to a receiver. It should be noted that since
characteristics of the term "channel" may differ according to
different wireless protocols, the term "channel" as used herein may
be considered as being used in a manner that is consistent with the
standard of the type of device with reference to which the term is
used. In some standards, channel widths may be variable (e.g.,
depending on device capability, band conditions, etc.). For
example, LTE may support scalable channel bandwidths from 1.4 MHz
to 20 MHz. In contrast, WLAN channels may be 22 MHz wide while
Bluetooth channels may be 1 Mhz wide. Other protocols and standards
may include different definitions of channels. Furthermore, some
standards may define and use multiple types of channels, e.g.,
different channels for uplink or downlink and/or different channels
for different uses such as data, control information, etc.
Band--The term "band" has the full breadth of its ordinary meaning,
and at least includes a section of spectrum (e.g., radio frequency
spectrum) in which channels are used or set aside for the same
purpose.
Automatically--refers to an action or operation performed by a
computer system (e.g., software executed by the computer system) or
device (e.g., circuitry, programmable hardware elements, ASICs,
etc.), without user input directly specifying or performing the
action or operation. Thus the term "automatically" is in contrast
to an operation being manually performed or specified by the user,
where the user provides input to directly perform the operation. An
automatic procedure may be initiated by input provided by the user,
but the subsequent actions that are performed "automatically" are
not specified by the user, i.e., are not performed "manually",
where the user specifies each action to perform. For example, a
user filling out an electronic form by selecting each field and
providing input specifying information (e.g., by typing
information, selecting check boxes, radio selections, etc.) is
filling out the form manually, even though the computer system must
update the form in response to the user actions. The form may be
automatically filled out by the computer system where the computer
system (e.g., software executing on the computer system) analyzes
the fields of the form and fills in the form without any user input
specifying the answers to the fields. As indicated above, the user
may invoke the automatic filling of the form, but is not involved
in the actual filling of the form (e.g., the user is not manually
specifying answers to fields but rather they are being
automatically completed). The present specification provides
various examples of operations being automatically performed in
response to actions the user has taken.
FIGS. 1 and 2--Communication System
FIG. 1 illustrates an exemplary (and simplified) wireless
communication system in which aspects of this disclosure may be
implemented, according to some embodiments. It is noted that the
system of FIG. 1 is merely one example of a possible system, and
embodiments of the disclosure may be implemented in any of various
systems, as desired.
As shown, the exemplary wireless communication system includes a
base station 102 which communicates over a transmission medium with
one or more (e.g., an arbitrary number of) user devices 106A, 106B,
etc., through 106N. Each of the user devices may be referred to
herein as a "user equipment" (UE). Thus, the user devices 106 are
referred to as UEs or UE devices.
The base station 102 may be a base transceiver station (BTS) or
cell site, and may include hardware and/or software that enables
wireless communication with the UEs 106A through 106N. If the base
station 102 is implemented in the context of LTE, it may
alternately be referred to as an `eNodeB`. The base station 102 may
also be equipped to communicate with a network 100. For example,
the network 100 may include a core network (potentially including
any number of core network slices) of a cellular service provider
(e.g., a public land mobile network (PLMN)). Alternatively or in
addition, the network 100 may include (or be coupled to) a
telecommunication network such as a public switched telephone
network (PSTN), the Internet, and/or various possibilities). Thus,
the base station 102 may facilitate communication among the user
devices and/or between the user devices and the network 100.
The communication area (or coverage area) of the base station may
be referred to as a "cell." The base station 102 and the UEs 106
may be configured to communicate over the transmission medium using
any of various radio access technologies (RATs), wireless
communication technologies, or telecommunication standards, such as
GSM, UMTS (WCDMA, TD-SCDMA), LTE, LTE-Advanced (LTE-A), 3GPP2
CDMA2000 (e.g., 1.times.RTT, 1.times.EV-DO, HRPD, eHRPD), Wi-Fi,
WiMAX etc.
Base station 102 and other similar base stations operating
according to the same or a different cellular communication
standard may thus be provided as a network of cells, which may
provide continuous or nearly continuous overlapping service to UEs
106A-N and similar devices over a geographic area via one or more
cellular communication standards. In other words, at least
according to some embodiments, the base station 102 may function as
a node in the radio access network (RAN) of a cellular network
operator.
Thus, while base station 102 may act as a "serving cell" for UEs
106A-N as illustrated in FIG. 1, each UE 106 may also be capable of
receiving signals from (and possibly within communication range of)
one or more other cells (which might be provided by other base
stations), which may be referred to as "neighboring cells". Such
cells may also be capable of facilitating communication between
user devices and/or between user devices and the network 100. Such
cells may include "macro" cells, "micro" cells, "pico" cells,
and/or cells which provide any of various other granularities of
service area size. Other configurations are also possible.
Note that a UE 106 may be capable of communicating using multiple
wireless communication standards. For example, a UE 106 might be
configured to communicate using two or more of GSM, UMTS, CDMA2000,
WiMAX, LTE, LTE-A, WLAN, Bluetooth, one or more global navigational
satellite systems (GNSS, e.g., GPS or GLONASS), one and/or more
mobile television broadcasting standards (e.g., ATSC-M/H or DVB-H),
etc. Other combinations of wireless communication standards
(including more than two wireless communication standards) are also
possible.
FIG. 2 illustrates user equipment 106 (e.g., one of the devices
106A through 106N) in communication with a base station 102,
according to some embodiments. The UE 106 may be a device with
cellular communication capability such as a mobile phone, a
hand-held device, a wearable device, a computer or a tablet, or
virtually any type of wireless device.
The UE 106 may include a processor that is configured to execute
program instructions stored in memory. The UE 106 may perform any
of the method embodiments described herein by executing such stored
instructions. Alternatively, or in addition, the UE 106 may include
a programmable hardware element such as an FPGA (field-programmable
gate array) that is configured to perform any of the method
embodiments described herein, or any portion of any of the method
embodiments described herein.
In some embodiments, the UE 106 may be configured to communicate
using any of multiple RATs. For example, the UE 106 may be
configured to communicate using two or more of GSM, UMTS, CDMA2000,
LTE, LTE-A, WLAN, or GNSS. Other combinations of wireless
communication technologies are also possible.
The UE 106 may include one or more antennas for communicating using
one or more wireless communication protocols or technologies. In
one embodiment, the UE 106 might be configured to communicate using
either of CDMA2000 (1.times.RTT/1.times.EV-DO/HRPD/eHRPD) or LTE
using a single shared radio and/or GSM or LTE using the single
shared radio. The shared radio may couple to a single antenna, or
may couple to multiple antennas (e.g., for MIMO) for performing
wireless communications. In general, a radio may include any
combination of a baseband processor, analog RF signal processing
circuitry (e.g., including filters, mixers, oscillators,
amplifiers, etc.), or digital processing circuitry (e.g., for
digital modulation as well as other digital processing). Similarly,
the radio may implement one or more receive and transmit chains
using the aforementioned hardware. For example, the UE 106 may
share one or more parts of a receive and/or transmit chain between
multiple wireless communication technologies, such as those
discussed above.
In some embodiments, the UE 106 may include separate transmit
and/or receive chains (e.g., including separate antennas and other
radio components) for each wireless communication protocol with
which it is configured to communicate. As a further possibility,
the UE 106 may include one or more radios that are shared between
multiple wireless communication protocols, and one or more radios
that are used exclusively by a single wireless communication
protocol. For example, the UE 106 might include a shared radio for
communicating using either of LTE or 1.times.RTT (or LTE or GSM),
and separate radios for communicating using each of Wi-Fi and
Bluetooth. Other configurations are also possible.
FIG. 3--Exemplary Block Diagram of a UE
FIG. 3 illustrates an exemplary block diagram of a UE 106,
according to some embodiments. As shown, the UE 106 may include a
system on chip (SOC) 300, which may include portions for various
purposes. For example, as shown, the SOC 300 may include
processor(s) 302 which may execute program instructions for the UE
106 and display circuitry 304 which may perform graphics processing
and provide display signals to the display 360. The processor(s)
302 may also be coupled to memory management unit (MMU) 340, which
may be configured to receive addresses from the processor(s) 302
and translate those addresses to locations in memory (e.g., memory
306, read only memory (ROM) 350, NAND flash memory 310) and/or to
other circuits or devices, such as the display circuitry 304,
wireless communication circuitry 330, connector I/F 320, and/or
display 360. The MMU 340 may be configured to perform memory
protection and page table translation or set up. In some
embodiments, the MMU 340 may be included as a portion of the
processor(s) 302.
As shown, the SOC 300 may be coupled to various other circuits of
the UE 106. For example, the UE 106 may include various types of
memory (e.g., including NAND flash 310), a connector interface 320
(e.g., for coupling to a computer system, dock, charging station,
etc.), the display 360, and wireless communication circuitry (e.g.,
radio) 330 (e.g., for LTE, Wi-Fi, GPS, etc.).
As noted above, the UE 106 may be configured to communicate
wirelessly using multiple wireless communication technologies. As
further noted above, in such instances, the wireless communication
circuitry 330 may include radio components which are shared between
multiple wireless communication technologies and/or radio
components which are configured exclusively for use according to a
single wireless communication technology. As shown, the UE device
106 may include at least one antenna (and possibly multiple
antennas, e.g., for MIMO and/or for implementing different wireless
communication technologies, among various possibilities), for
performing wireless communication with cellular base stations
and/or other devices. For example, the UE device 106 may use
antenna(s) 335 to perform the wireless communication.
As described further subsequently herein, the UE 106 may include
hardware and/or software components for implementing and/or
supporting implementation of features described herein. The
processor 302 of the UE device 106 may be configured to implement
part or all of the methods described herein, e.g., by executing
program instructions stored on a memory medium (e.g., a
non-transitory computer-readable memory medium). In other
embodiments, processor 302 may be configured as a programmable
hardware element, such as an FPGA (Field Programmable Gate Array),
or as an ASIC (Application Specific Integrated Circuit).
Alternatively (or in addition) the processor 302 of the UE device
106, in conjunction with one or more of the other components 300,
304, 306, 310, 320, 330, 335, 340, 350, 360 may be configured to
implement part or all of the features described herein.
FIG. 4--Exemplary Block Diagram of a Base Station
FIG. 4 illustrates an exemplary block diagram of a base station
102. It is noted that the base station of FIG. 4 is merely one
example of a possible base station. As shown, the base station 102
may include processor(s) 404 which may execute program instructions
for the base station 102. The processor(s) 404 may also be coupled
to memory management unit (MMU) 440, which may be configured to
receive addresses from the processor(s) 404 and translate those
addresses to locations in memory (e.g., memory 460 and read only
memory (ROM) 450) or to other circuits or devices.
The base station 102 may include at least one network port 470. The
network port 470 may be configured to couple to a telephone network
and provide a plurality of devices, such as UE devices 106, access
to the telephone network as described above in FIGS. 1 and 2.
The network port 470 (or an additional network port) may also or
alternatively be configured to couple to any of various possible
cellular network entities, e.g., including one or more core network
instances or core network slices of a cellular service provider, a
network slice selection function, and/or various other possible
cellular network entities. The core network(s) may provide mobility
related services and/or other services to a plurality of devices,
such as UE devices 106. In some cases, the network port 470 may
couple to a telephone network via the core network(s), and/or the
core network(s) may provide a telephone network (e.g., among other
UE devices serviced by the cellular service provider).
The base station 102 may include at least one antenna 434, and
possibly multiple antennas. The antenna(s) 434 may be configured to
operate as a wireless transceiver and may be further configured to
communicate with UE devices 106 via radio 430. The antenna(s) 434
communicates with the radio 430 via communication chain 432.
Communication chain 432 may be a receive chain, a transmit chain or
both. The radio 430 may be configured to communicate via various
wireless telecommunication standards, including, but not limited
to, LTE, LTE-A, UMTS, CDMA2000, Wi-Fi, etc.
The BS 102 may be configured to communicate wirelessly using
multiple wireless communication standards. In some instances, the
base station 102 may include multiple radios, which may enable the
base station 102 to communicate according to multiple wireless
communication technologies. For example, as one possibility, the
base station 102 may include an LTE radio for performing
communication according to LTE as well as a Wi-Fi radio for
performing communication according to Wi-Fi. In such a case, the
base station 102 may be capable of operating as both an LTE base
station and a Wi-Fi access point. As another possibility, the base
station 102 may include a multi-mode radio which is capable of
performing communications according to any of multiple wireless
communication technologies (e.g., LTE and Wi-Fi, LTE and UMTS, LTE
and CDMA2000, UMTS and GSM, etc.).
The BS 102 may be configured to act as a node of a radio access
network (RAN) of a cellular network. Thus, the BS 102 may provide
radio access to the cellular network (e.g., including one or more
core network instances, as previously noted) to wireless devices.
According to some embodiments, the BS 102 may be configured to
implement multiple possible RAN slices, e.g., to accomodate
different scenarios with respect to RAN functionality, performance,
isolation, etc. The different RAN slices may include different sets
of RAN functions, and/or differently configured RAN functions
(e.g., having different resource pools, etc.).
As described further subsequently herein, the BS 102 may include
hardware and software components for implementing and/or supporting
implementation of features described herein. The processor 404 of
the base station 102 may be configured to implement or support
implementation of part or all of the methods described herein,
e.g., by executing program instructions stored on a memory medium
(e.g., a non-transitory computer-readable memory medium).
Alternatively, the processor 404 may be configured as a
programmable hardware element, such as an FPGA (Field Programmable
Gate Array), or as an ASIC (Application Specific Integrated
Circuit), or a combination thereof. Alternatively (or in addition)
the processor 404 of the BS 102, in conjunction with one or more of
the other components 430, 432, 434, 440, 450, 460, 470 may be
configured to implement or support implementation of part or all of
the features described herein.
FIG. 5--Exemplary Block Diagram of a Network Element
FIG. 5 illustrates an exemplary block diagram of a network element
500, according to some embodiments. According to some embodiments,
the network element 500 may implement one or more logical
functions/entities of a cellular core network, such as a mobility
management entity (MME), serving gateway (S-GW), etc. As another
possibility, the network element 500 may implement a network slice
selection function (NSSF) entity. It is noted that the network
element 500 of FIG. 5 is merely one example of a possible network
element 500. As shown, the core network element 500 may include
processor(s) 504 which may execute program instructions for the
core network element 500. The processor(s) 504 may also be coupled
to memory management unit (MMU) 540, which may be configured to
receive addresses from the processor(s) 504 and translate those
addresses to locations in memory (e.g., memory 560 and read only
memory (ROM) 550) or to other circuits or devices.
The network element 500 may include at least one network port 570.
The network port 570 may be configured to couple to one or more
base stations and/or other cellular network entities and/or
devices. The network element 500 may communicate with base stations
(e.g., eNBs) and/or other network entities/devices by means of any
of various communication protocols and/or interfaces.
As described further subsequently herein, the network element 500
may include hardware and software components for implementing
and/or supporting implementation of features described herein. The
processor(s) 504 of the core network element 500 may be configured
to implement or support implementaiton of part or all of the
methods described herein, e.g., by executing program instructions
stored on a memory medium (e.g., a non-transitory computer-readable
memory medium). Alternatively, the processor 504 may be configured
as a programmable hardware element, such as an FPGA (Field
Programmable Gate Array), or as an ASIC (Application Specific
Integrated Circuit), or a combination thereof.
Network Slicing
Network slicing is a concept that may enable a cellular network
operator to create customized networks to provide solutions for
different market scenarios that have diverse requirements, e.g., in
the areas of functionality, performance and isolation. For example,
a cellular network may provide multiple network slices, of which
each network slice may include a set of network functions (NFs)
selected to provide some specific telecommunication service(s) and
network capabilities, and the resources to run these NFs.
Network slicing techniques are currently actively under development
and may figure prominently in fifth generation ("5G") cellular
communication technologies. For example, global and regional
organizations such as next generation mobile networks (NGMN), third
generation partnership project (3GPP), 5G public private
partnership (5GPPP), 4G Americas, 5G Forum, International Mobile
Telecommunications 2020 (IMT-2020), etc., have documented possible
use cases and requirements regarding network slicing.
Among the possible network slicing solutions, Radio Access Network
(RAN) slicing and Core Network (CN) slicing are both possible and
are currently under study by 3GPP RAN working groups (WGs) and 3GPP
service and system aspects (SA) WGs separately. For example, 3GPP
TR 23.799 is maintained by 3GPP SA2, and describes several
candidate solutions for 5G network architecture and related key
issues, including network slicing.
According to some embodiments, a number of key principles may be
followed to support network slicing in a RAN. For example, at least
in some instances, some or all of the following principles may be
followed.
As one possible principle, the RAN may be aware of the possibility
of network slices. For example, a RAN may be expected to support
differentiated handling of different network slices that have been
pre-configured by the operator.
As another possible principle, the RAN may be expected to support
the selection of the RAN part of the network slice by an index or
ID provided by the UE. The index or ID may unambiguously identify
one of the pre-configured network slices in the PLMN.
A further principle may relate to resource management between
slices. For example, the RAN may be expected to support policy
enforcement between slices as per service level agreements.
Yet another principle may relate to support of Quality of Service
(QoS). For example, the RAN may be expected to support QoS
differentiation within a slice.
A still further principle may relate to RAN selection of a CN
entity. For example, the RAN may be expected to support initial
selection of the CN entity for initial routing of uplink messages
based on received slice index and a mapping in the RAN node (CN
entity, slices supported).
Another possible principle may relate to resource isolation between
slices. For example, the RAN may be expected to support resource
isolation between slices.
Variations on the above principles and/or alternative principles
are also possible. Furthermore, note that, at least according to
some embodiments, the manner in which a RAN supports the slice
enabling in terms of RAN functions (i.e., the set of network
functions that form each slice) may be implementation dependent,
e.g., provided the generally agreed upon principles for supporting
network slicing are upheld.
FIGS. 6-13 illustrate various possible network slice selection
logical architectures and associated procedures. Note that FIGS.
6-13 and the information provided herein below in conjunction
therewith are provided by way of example, and are not intended to
be limiting to the disclosure as a whole. Numerous variations and
alternatives to the details provided herein below are possible and
should be considered within the scope of the disclosure.
FIG. 6--First Network Slice Selection Solution
FIG. 6 illustrates one possible cellular network logical
architecture that may support network slice selection. The
illustrated architecture and associated procedures and details of
FIG. 6 may be referred to herein as a "first solution". According
to this architecture and function, it is assumed that any slicing
of a PLMN 620 is not visible to the UEs (e.g., UE 622) at the radio
interface. Additionally, it is assumed according to this
architecture and function that the RAN (e.g., general RAN 624) is
not sliced.
As shown, according to the architecture of FIG. 6, a slice
selection and routing function 626 is defined to link the radio
access bearer(s) of a UE 622 with the appropriate core network
instance. Notable characteristics of the architecture of FIG. 6 may
include that the RAN 624 appears as one RAT+PLMN to the UE 622, and
that any association with a particular network instance is
performed by network 620 internally.
According to the architecture of FIG. 6, the illustrated slice
selection and routing function 626 may be provided by the RAN 624
or by the CN. The slice selection and routing function 626 may
route signaling between the RAN 624 and the selected CN instance
based on information provided by the UE 622 and possibly based on
CN provided information.
FIG. 7--Second Network Slice Selection Solution
FIG. 7 illustrates another possible cellular network logical
architecture that may support network slice selection. The
illustrated architecture and associated procedures and details of
FIG. 7 may be referred to herein as a "second solution". This
second solution proposes that a multi-dimensional descriptor (e.g.
application, service descriptor) is configured in a UE (e.g., one
of the illustrated UEs 722A-C). The UE 722 may report the
multi-dimensional descriptor to the network. Based on this
multidimensional descriptor provided by the UE 722, and on other
information (e.g. subscription information) available in the
network, the relevant functions within a certain network slice can
be selected.
Multiple network slice and function selection options may be
possible according to the architecture of FIG. 7. For example, a
two step selection mechanism or a one step selection mechanism may
be used for selecting a core network slice and for selecting
network functions within the selected network slice.
According to the two-step selection mechanism, a selection function
in the RAN 724 may use the application ID (e.g., part of the
multidimensional descriptor), along with information (e.g.
subscription information) available in the network, to select the
appropriate core network slice (e.g., one of the core network
slices 728, 730, 732). A selection function within the core network
may use the service descriptor (e.g., part of the multidimensional
descriptor) to select the appropriate network functions within the
network slice.
According to the one-step selection mechanism, a selection function
within the RAN 724 or within the core network may use the
application ID and the service descriptor (e.g., parts of the
multi-dimensional descriptor), along with information (e.g.
subscription information) available in the network, to select the
appropriate network slice (e.g., one of the core network slices
728, 730, 732) and network functions. The selection function may
then (re-)direct the UE 722 accordingly.
FIGS. 8-9--Third Network Slice Selection Solution
FIG. 8 illustrates a further possible cellular network logical
architecture that may support network slice selection, while FIG. 9
illustrates possible signal flow procedure details associated with
the architecture of FIG. 8. The illustrated architecture of FIG. 8
and associated procedures and details of FIG. 9 may be referred to
herein as a "third solution". According to this architecture and
function, as shown, a single set of control plane (or "c-plane" or
"CP") functions (e.g., including C-CPF-1 830, etc.) that are in
common among multiple core network instances (e.g., core network
instance 1 (CNI-1), core network instance 2 (CNI-2)) is shared
across the core network instances. Other c-plane functions that are
not in common among the core network instances reside in their
respective core network instances (e.g., CPF-1 832 within CNI-1,
CPF-1 836 within CNI-2, etc.), and are not shared with other core
network instances. Similarly, different core network instances may
include different user plane (or "u-plane" or "UP") functions
(e.g., UPF-1 834 within CNI-1, UPF-1 838 within CNI-2), etc.).
According to the architecture of FIG. 8, a set of c-plane functions
may be responsible, for example, for supporting UE mobility if
demanded or for admitting the UE 822 into the network by performing
authentication and subscription verification.
The network slice selection function (NSSF) 826 illustrated in FIG.
8 may be responsible for selecting a core network instance to
accommodate the UE 822, e.g., by taking into account the UE's
subscription characteristics and any session specific parameters,
e.g., the UE Usage Type.
The c-plane selection function (CPSF) 828 illustrated in FIG. 8 may
be responsible for selecting with which c-plane functions within
the selected core network instance the RAN node (e.g., base
station) 824 serving the UE 822 should communicate. This selection
of c-plane functions may depend on session specific parameter(s),
e.g., UE Usage Type.
FIG. 9 illustrates possible signal flow procedures associated with
the network slice selection logical architecture of FIG. 8 (e.g.,
associated with the third solution). The illustrated signal flow
procedures include a possible signal flow for a mobility management
attach procedure (part 1: steps 901-906) and possible signal flows
for session management (part 2: steps 907-916, including part 2.1:
steps 907-911, and part 2.2: steps 912-916).
As shown, in step 901, when a UE 822 first connects to the
operator's network, it sends a network connection request to the
RAN node 824. If the UE 822 provides enough information to the RAN
node 824 to route the message to the appropriate core network
instance and its corresponding c-plane function, the RAN node 824
routes this request to this c-plane function. Hence, the flow
continues in step 904. Otherwise, the RAN node 824 forwards it to
the NSSF/CPSF 826/828, and the flow continues in step 902.
In step 902, the NSSF/CPSF 826/828 determines which core network
instance and its corresponding c-plane function(s) are to be
connected to by taking into account information in the request from
a UE 822 in step 901. In addition, other information from the
subscription database may be also considered. In this signal flow
example depicted in FIG. 9, this is the core network instance #1
(CNI-1), which may include common c-plane functions (C-CPF-1) 830
and CNI-1 specific c-plane functions (CPF-1) 832. Note that CNI-1
may also include certain user plane (u-plane or UP) functions
(UPF-1) 834.
In step 903, the NSSF/CPSF 826/828 sends a response to the RAN node
824 with the selected C-CPF-1 830/CPF-1 832 of the selected
CNI-1.
In step 904, based on the response sent in step 903, the RAN node
824 selects c-plane functions (e.g., C-CPF-1 830, CPF-1 832) of the
selected CNI-1.
In step 905, the RAN node 824 forwards the network connection
request from the UE 822 to this C-CPF-1 830, (e.g., which was
included among the selected c-plane functions from steps 903 and
step 904).
In step 906, authentication and admitting the UE 822 into the
selected CNI-1 is performed.
In step 907, the UE 822 provides a request to RAN node 824 for a
communication service (e.g., "service #1" that is provided by the
CNI-1).
In step 908, the RAN node 824 forwards the request for service to
the C-CPF-1 830.
In step 909, the C-CPF-1 830 selects CPF-1 832 of the CNI-1 and
forwards the request for the service #1 to this CPF-1 832
In step 910, after a successful session establishment, the CPF-1
832 in CNI-1 sends the session response back to C-CPF-1 830.
In step 911, the C-CPF-1 830 sends a new service response back to
the UE 822 via the RAN node 824.
In step 912, the UE 822 provides a request to RAN node 824 for a
new communication service that is of a different service type
(e.g., "service #2) than the previous service. A different core
network instances (core network instance #2 (CNI-2)) may be
selected for this new communication service. Note that CNI-2 may
include common c-plane functions 830 (e.g., in common with CNI-1)
and CNI-2 specific c-plane functions (CPF-1) 836. Note that CNI-2
may also include certain u-plane functions (UPF-1) 838.
In step 913, the RAN node 824 forwards the request for new
communication service to the C-CPF-1 830.
In step 914, the C-CPF-1 830 selects CPF-1 836 of the CNI-2 and
forwards the request for the service #2 to this CPF-1 836 in
CNI-2.
In step 915, after a successful session establishment, the CPF-1
836 in CNI-2 sends the session response back to C-CPF-1 830.
In step 916, the C-CPF-1 830 sends a new service response back to
the UE 822 via the RAN node 824.
FIGS. 10-11--Fourth Network Slice Selection Solution
FIG. 10 illustrates a still further possible cellular network
logical architecture that may support network slice selection,
while FIG. 11 illustrates possible signal flow procedure details
associated with the architecture of FIG. 10. The illustrated
architecture of FIG. 10 and associated procedures and details of
FIG. 11 may be referred to herein as a "fourth solution".
According to this architecture and function, an Access Control
Agent (ACA) 1026 is a common control plane network function which
has the following key functions. The ACA 1026 may operate as
authenticator to support the mobile network operator (MNO)
authentication and authorization of the UE 1022 to access the
NextGen core. The ACA 1026 may select the NextGen Core network
slice instance 1030 to serve the UE's service request. The ACA 1026
may forward the NGNAS signaling to the UE's serving network slice's
control plane network functions once the network slice session is
setup. The ACA 1026 may support the NextGen Core's network slice
instance 1030 binding with the NextGen Access 1024. The ACA 1026
may support roaming (e.g., coordinated with the network slice
instance 1030 selected from the visiting or home NextGen Core).
During the UE initial attach, the ACA 1026 may initiate procedures
that are used to identify, authenticate, and authorize the UE. Once
the UE 1022 has been successfully authenticated via the support of
ACA 1026, the ACA 1026 may update the home subscriber server (HSS)
1028 with the information of the UE 1022 and may also request the
subscriber profile of the UE 1022, e.g., to be stored in its cache.
A unique short temporary identity (e.g., referred as A-TMSI) may be
assigned to the UE 1022 to identify the UE's context in ACA's cache
corresponding to the UE's subscriber profile.
The UE subscription information fetched from the HSS may include
the pre-provisioned UE's eligible NG Service Type(s) (e.g.,
vehicle-to-X (V2X), embedded mobile broadband (eMBB), etc.) that
indicate the type of network services that have been subscribed by
the UE 1022, terminal capabilities, etc.
Once the UE 1022 is successfully authenticated and the NAS security
association is established with the NextGen Core, the UE 1022 may
initiate a NG Service Session Request, which may include NG Service
Type information and Request Resource Allocation information. The
ACA 1026 may refer to certain required UE's network slice instance
selection information (e.g., UE's capability, UE's location, the
policy of UE's home PLMN and the NG Service Type information, etc.)
to select the appropriate Network Slice instance 1030 and to
trigger the NG Service Initiation Request, which will then initiate
the NG Service Session Establishment for the UE 1022 for the target
network service. The ACA 1026 may need to consult with HSS 1028 to
verify the eligibility of the NG Service Type that is provided by
the UE 1022.
Note that the NG Service Session Establishment procedures may
include network slice instance access authentication, session and
mobility anchor establishment, QoS management and NG Service
Session Binding with the NextGen access 1024, etc.
FIG. 11 illustrates signal flow procedures associated with the
network slice selection logical architecture of FIG. 10 (e.g.,
associated with the fourth solution).
As shown, in step 1101, a UE 1022 may establish connectivity to the
NextGen Access 1024 at the RRC layer.
In step 1102, the UE 1122 may initiate a NGNAS Attach Request to
establish connectivity with the NextGen Core over the RRC
connectivity. As part of this, the NextGen Access node 1024 may
select the appropriate ACA 1026 for the NGNAS Attach Request. In
other words, the NextGen Access node 1024 may select the target ACA
1026 to serve the UE 1022.
In step 1103, if the ACA 1026 is not able to identify the UE 1022
with the identity given in the NGNAS Attach Request message, the
ACA 1026 may initiate an Identity Request to the UE 1022. The UE
1022 may respond back with its identity in an Identity Response
message to the ACA 1026. After successful authentication, the
network may initiate a Security mode command to encrypt the NGNAS
message between the UE 1022 and the ACA 1026, e.g., to protect the
privacy of the subscriber. Subsequent NGNAS messages may thus be
integrity protected.
In step 1104, after the successful authentication, the ACA 1026 may
update the HSS 1028 with the context of the UE 1022, e.g., using an
Update Location Request message, and may also include a request for
the subscriber profile for this UE 1022 from the HSS 1028. The HSS
1028 may update its database with the current context of the UE
1022 and respond to ACA 1026 with the subscriber profile of the UE
1022, if requested, in the Update Location Acknowledge message.
In step 1105, the ACA 1026 may respond to the UE 1022 with a
successful NGNAS Attach Response.
In step 1106, the UE 1022 may initiate a NG Service Session Request
to its serving ACA 1026, which may include its target NG Service
type and Resource Allocation request information.
In step 1107, the ACA 1026 may refer to the required network slice
instance selection information (e.g., UE's capability, UE's
location, UE's HPLMN policy and the NG Service Type information
etc.) to select the appropriate network slice instance 1030 to
trigger the NS Service Initiation Request for the UE 1022.
In step 1108, the UE 1022 may perform the NG Service Session
Establishment procedures with the network functions within the
network slice instance 1030, the NextGen Access 1024 and the UE
1022.
FIGS. 12-13--Proposed Network Slice Selection Solution
The previously described logical architectures supporting network
slicing (i.e., encompassing the first, second, third, and fourth
solutions) may suffer from a variety of limitations. For example,
in the first and fourth solutions, all signaling is routed through
the slice selection and routing function or the access control
agent respectively. In addition, in the first solution, user data
is also routed through the slice selection and routing function.
Such architectures may be relatively inflexible and may be forced
to provide particularly robust and powerful network slice selection
entities and/or may potentially suffer from a data and/or signaling
bottleneck or even breakdown. The second solution provides network
slice selection techniques only in a general manner, does not
include any specific procedure details for network slice selection,
and does not clearly provide means for a communication device to
connect to multiple (e.g., different) network slices. The third
solution assumes that common control plane functions exist for
different network slices, which may impose a potentially
undesirable rigidity to the architecture.
Accordingly, FIG. 12 illustrates a possible cellular network
logical architecture that may support network slice selection in a
manner that addresses such limitations, while FIG. 13 illustrates
possible signal flow procedure details associated with the
architecture of FIG. 12. Thus, the illustrated architecture of FIG.
12 and associated procedures and details of FIG. 13 may be referred
to herein as a "proposed architecture" and/or "proposed
solution".
As shown, the network slice selection logical architecture of FIG.
12 includes a UE 1222, a radio access network (RAN) node 1224, a
Network Slice Selection Function (NSSF) 1226, and a user
subscription information repository (e.g., HSS) 1228. The NSSF 1226
may include an interface to the RAN node 1224 and an interface to
the HSS 1228. The NSSF may be responsible for selecting a Network
Slice for a particular UE connection upon request by the RAN node
1224, e.g., based on user subscription information from the HSS and
the network operator's policies. As further shown, the proposed
architecture may include multiple core network slices (e.g., NS1
1230, NS2 1240, etc.). The RAN node 1224 may also implement
multiple (e.g., virtual) RAN slices, at least according to some
embodiments.
As shown, there may be one Control Plane (CP) entry point (e.g., CP
entry points 1232, 1242) for each respective network slice. The
NSSF 1226 may store addresses (e.g., IP addresses) for these CP
entry points, e.g., in pairs with corresponding Network Slice IDs.
The network slice ID and address pair selected by the NSSF 1226 for
a given UE connection request, e.g., from UE 1222, may be sent to
the RAN node 1224 by the NSSF 1226 in a Network Slice selection
response. The RAN node may store this pair in UE context
information for the UE 1222 and request connection to the specified
CP entry point for the UE 1222.
According to some embodiments, the UE 1222 may optionally indicate
a preferred Network Slice ID (NSID) to the network. For example, as
one possibility, if a UE preferred NSID is provided and matches the
selection policy used by the network, the preferred NSID may be
chosen by the NSSF 1226 as having highest priority among all
matching NSIDs, while if no UE preferred NSID is provided or if the
provided UE preferred NSID does not match the selection policy used
by the network, the NSSF 1226 may select a different NSID (e.g.,
one with a highest priority among all matching NSIDs) for the UE
1222.
According to some embodiments, the UE 1222 may be able to connect
to more than one network slice at the same time. For example, each
time the UE 1222 requests a new connection or new service, the RAN
node 1224 may query the NSSF 1226 for an appropriate Network Slice
ID for the new connection/service and may establish a connection
with the selected network slice via its CP entry point. Thus, the
UE 1222 may be capable of communicating with multiple network
slices (e.g., NS1 1230 and NS2 1240) in an at least partially
temporally overlapping manner.
FIG. 13 illustrates signal flow procedures associated with the
network slice selection logical architecture of FIG. 12 (e.g.,
associated with the proposed solution). The illustrated signal flow
procedures include a possible signal flow for a first service
request (part 1: steps 1301-1311) and for a second service request
(part 2: steps 1312-1319).
As shown, in step 1301, the UE 1222 and RAN node 1224 may establish
an access stratum (AS) connection, e.g., including setting up one
or more radio resource control (RRC) bearers. According to some
embodiments, the RAN node 1224 may broadcast (e.g., in a master
information block (MIB), system information block (SIB), etc.) one
or more network slice IDs (NSIDs) core network slice IDs (CNSIDs)
and/or radio access network slice IDs (RANSIDs) associated with
network slices supported by the RAN node 1224. The UE 1222 may
consider this information during cell selection, and at least in
some instances, may select a serving cell (e.g., RAN node 1224)
based at least in part on the network slices indicated to be
available from that serving cell.
In step 1302, the UE 1222 may provide a non-access stratum (NAS)
connection request message to the selected RAN node 1224. The NAS
connection request may function as a ("first") service request,
e.g., for requesting a connection to obtain a particular service
from the network. The NAS connection request may include any of
various types of information, potentially including but not limited
to a UE ID, a Service Type, Application ID, etc. Optionally, the UE
1222 may include an indication of one or more preferred network
slices (e.g., a UE preferred NSID) in the message.
In step 1303, the RAN node 1224 may send a network slice selection
request message to the NSSF 1226, which may include any or all of
the information obtained from the UE 1222 in step 1301, e.g., UE
ID, Service Type, Application ID, UE preferred NSID, RAN node ID,
etc.
In step 1304, the NSSF 1226 may determine whether it has valid
subscription data and/or network slice selection related data for
the UE 1222. Note that the NSSF 1226 may determine whether any
available data for the UE 1222 is valid in any of various manners,
as desired; as one possibility, a timer may be initiated when the
data is first obtained, and the data may be considered valid until
expiration of the timer, after which the data may no longer be
considered valid. If the NSSF 1226 determines that it does not have
valid subscription data and/or network slice selection related data
for the UE 1222 (or does not have sufficient valid data to make a
network slice selection for the UE 1222), the NSSF 1226 may request
subscription data and/or network slice selection related data for
the UE 1222 from the subscription repository (e.g. HSS) 1228.
In step 1305, the HSS 1228 may provide the requested data to the
NSSF 1226. The NSSF 1226 may store the data received from the HSS
1228, and (and least in some instances) may start a timer or
otherwise initiate a mechanism for monitoring the validity of the
data stored for the UE 1222.
In step 1306, the NSSF 1226 may select a network slice for the UE
1222. The network slice may be selected based on any or all of the
network operator's network slice selection policies, information
relating to physical and/or subscription characteristics of the UE
1222, and/or information relating to the first service request,
among various considerations, and may include information received
from the UE 1222 by way of the RAN node 1224 in step 1303,
information received from the HSS 1228 in step 1305, and/or
information stored by the NSSF 1226.
According to some embodiments, a NSID may include a RANSID and a
CNSID. At least in some instances, if a UE preferred NSID is
provided and is compatible with the selection policy, the UE
preferred NSID may be given the highest priority among all matching
NSIDs, and may be selected. If the UE preferred NSID is not
compatible with the selection policy, the NSSF 1226 may select a
different NSID (e.g., a NSID with highest priority among all
matching NSIDs). As previously noted, a Network Slice ID may be
associated with a single CP entry point, and may further be
associated with a set of CP Network Functions and UP Network
Functions.
In step 1307, the NSSF 1226 may provide a network slice selection
response (result) message to the RAN node 1224, which may indicate
the selected NSID (e.g., NSID1 in the example signal flow of FIG.
13) and associated IP address information for the selected CP entry
point (e.g., NS1 CP entry point 1232 in the example signal flow of
FIG. 13). Note that since each NSID may include a CNSID and a
RANSID, at least according to some embodiments, the network slice
selection response may implicitly indicate a specific ("first")
core network slice and a specific ("first") radio access network
slice. As another possibility, the network slice selection response
may explicitly include an indication of a selected "first" core
network slice and/or "first" radio access network slice for the
first service request.
In step 1308, the RAN node 1224 may provide a connection request
message to the NS1 CP entry point 1232. The connection request
message may include the NAS connection request message, e.g., with
the selected NSID1 and RAN node ID. The RAN node 1224 may establish
UE context with its selected NSID1 and the NS1 CP entry point IP
address. The RAN node 1224 may also associate the UE 1222 to a
NSID1 resource pool, and accordingly provide RAN resources to the
UE 1222 from the NSID1 resource pool (e.g., at least in association
with the first service request).
In step 1309, the NS1 CP entry point 1232 may execute the
connection establishment procedure, e.g., as may be pre-defined for
the selected NSID1. The connection establishment procedure may be
network slice specific, and may involve different network functions
(e.g., other NFs in NS1 1234). According to some embodiments, the
connection establishment procedure may include any or all of
authentication, temporary ID allocation, IP address allocation,
session establishment, and/or any of various other elements.
In step 1310, the NS1 CP entry point 1232 may provide a connection
establishment response message to the RAN node 1224, which may
carry the NAS connection establishment response and one or more
addresses for other NFs in NS1 (e.g., UP NF1 IP address, etc.). The
RAN node 1224 may update the UE context to add such routing
information (e.g., UP NF1 IP address, corresponding AS connection,
etc.).
In step 1311, the RAN node 1224 may send the NAS connection
establishment response to the UE 1222, which may include such
information as a temporary UE ID, an IP address allocated for the
UE 1222, and/or other NAS connection related information for the UE
1222.
In step 1312, the UE 1222 may provide a new service request message
to the RAN node 1224. The new service request message may function
as a "second" service request, e.g., for requesting a connection to
obtain a particular service (e.g., different from the first
service) from the network. The new service request may include any
of various types of information potentially including but not
limited to a UE ID, Service Type, Application ID, etc. Optionally,
the UE 1222 may include an indication of one or more preferred
network slices (e.g., a UE preferred NSID) in the message.
In step 1313, the RAN node 1224 may send a network slice selection
request message to the NSSF 1226, which may include any or all of
the information obtained from the UE 1222 in step 1312, e.g., UE
ID, Service Type, Application ID, UE preferred NSID, RAN node ID,
etc.
In step 1314, the NSSF 1226 may determine whether it has valid
subscription data and/or network slice selection related data for
the UE 1222. Since such information may have been previously
obtained (e.g, in steps 1304 and 1305), in this case the NSSF 1226
may have valid subscription data and network slice selection
related data for the UE 1222 stored. Additionally, the NSSF 1226
may select a network slice for the UE 1222 for the second service
request. The network slice may be selected based on any or all of
the network operator's network slice selection policies,
information relating to physical and/or subscription
characteristics of the UE 1222, and/or information relating to the
first service request, among various considerations, and (in this
case) may include information received from the UE 1222 by way of
the RAN node 1224 in step 1313 and the subscription data and
network slice selection related data stored by the NSSF 1226.
In step 1315, the NSSF 1226 may provide a network slice selection
response (result) message to the RAN node 1224, which may indicate
the selected NSID (e.g., NSID2 in the example signal flow of FIG.
13) and associated IP address information for the selected CP entry
point (e.g., NS2 CP entry point 1242 in the example signal flow of
FIG. 13. Since each NSID may include a CNSID and a RANSID, at least
according to some embodiments, the network slice selection response
may implicitly indicate a specific ("second") core network slice
and a specific ("second") radio access network slice. As another
possibility, the network slice selection response may explicitly
include an indication of a selected "second" core network slice
and/or "second" radio access network slice for the second service
request.
In step 1316, the RAN node 1224 may provide a connection request
message to the NS2 CP entry point 1242. The connection request
message may include the new service request message, e.g., with the
selected NSID2 and RAN node ID. The RAN node 1224 may update the UE
context, e.g., adding NSID2 and the NS2 CP entry point IP address.
The RAN node 1224 may also associate the new connection of the UE
1222 to a NSID2 resource pool, and accordingly provide RAN
resources to the UE 1222 from the NSID2 resource pool (e.g., at
least in association with the second service request).
In step 1317, the NS2 CP entry point 1242 may execute the
connection establishment procedure, e.g., as may be pre-defined for
the selected NSID2. The connection establishment procedure may be
network slice specific, and may involve different network functions
(e.g., other NFs in NS2 1244).
In step 1318, the NS2 CP entry point 1242 may send a connection
establishment response message to the RAN node 1224, which may
carry the NAS Service Response and one or more addresses for other
NFs in NS2 (e.g., UP NF2 IP address, etc.). The RAN node 1224 may
update the UE context to add such new routing information (e.g., UP
NF2 IP address, corresponding AS connection, etc.).
In step 1319, the RAN node 1224 may send the NAS service response
to the UE 1222.
As previously noted, the proposed solution may provide a number of
benefits relative to the previously described (i.e., first, second,
third, and fourth) solutions. For example, the proposed solution
may demand relatively little processing capability of the network
slice selection function, as no signaling or data routing is asked
of the NSSF. Further, the proposed architecture may be inherently
relatively robust, as even if the NSSF were to (e.g., temporarily)
break down, it may still be possible to establish a connection for
a UE, e.g., to a default network slice and/or a network slice with
which the UE has an existing connection. Additionally, the network
functions and their interfaces/procedures for each network slice
are defined within the network slice, e.g., through a management
and orchestration system. This may simplify the logic between
different network slices, and may allow for more flexibility of
network slicing deployment use cases (e.g., as network slices don't
have to rely on common CP functions.).
In the following section, certain features of the proposed solution
and the first, second, third, and fourth solutions are compared and
contrasted for illustrative purposes.
All signaling and data will go through the slice selection and
routing function in the first solution. As previously noted, this
may require the slice selection and routing function to be very
strongly robust and to have substantial processing capabilities.
The NSSF in the proposed solution may (at least according to some
embodiments) be used only for network slice selection and may not
process UE NAS messages or route UP data.
The second solution describes general ways for selecting a network
slice for a UE. In comparison, the proposed solution supports UEs
connecting to multiple different network slices, and includes a
detailed connection establishment procedure.
The third solution is based on assumption that common CP functions
exist for different network slices. The proposed solution does not
require any such assumption. Additionally, in the third solution,
the CP function(s) in a network slice instance to which the RAN
node connects are selected by RAN node. In comparison, in the
proposed solution, the CP function to which the RAN node connects
may be indicated by the NSSF. Further, in the third solution, the
service request message is always sent to the common CP function by
the RAN node, while in the proposed solution, the service request
message may be sent to the CP entry point of the selected network
slice.
The ACA in the fourth solution may represent the CP anchor for the
UE, such that all NAS CP messages may be routed through this ACA
function. In contrast, the NSSF in the proposed solution may (at
least according to some embodiments) be used only for network slice
selection and may not process UE NAS messages.
In the following further exemplary embodiments are provided.
One set of embodiments may include an apparatus, comprising: a
processing element configured to cause a network slice selection
function (NSSF) cellular network entity of a cellular network to:
receive a network slice selection request associated with a service
request by a wireless device; select a network slice of the
cellular network in response to the network slice selection
request; and provide a network slice selection response, wherein
the network slice selection response indicates a control plane
entry point address for the selected network slice.
According to some embodiments, selecting the network slice is based
at least in part on information received from the wireless device
by way of the service request.
According to some embodiments, the information received from the
wireless device comprises an indication of a preferred network
slice, wherein the indication of the preferred network slice is
used when selecting the network slice.
According to some embodiments, the processing element is further
configured to cause the NSSF to: request user subscription
information for the wireless device from a user subscription
information repository of the cellular network; and receive user
subscription information for the wireless device from the user
subscription information repository, wherein selecting the network
slice is based at least in part on the user subscription
information received from the user subscription information
repository.
According to some embodiments, the processing element is further
configured to cause the NSSF to: store the user subscription
information for the wireless device for at least a period of time
in which the stored user subscription information is considered
valid; and perform network slice selections for the wireless device
during the period of time in which the stored user subscription
information is considered valid based at least in part on the
stored user subscription information.
According to some embodiments, the network slice selection request
is received from a radio access network (RAN) node of the cellular
network, wherein the network slice selection response is provided
to the RAN node of the cellular network, wherein the cellular
network entity does not process user plane data for the wireless
device.
According to some embodiments, the network slice selection response
further indicates a selected set of control plane network functions
and user plane network functions of the selected network slice.
According to some embodiments, the selected network slice comprises
a radio access network (RAN) slice and a core network (CN)
slice.
A further set of embodiments may include a non-transitory computer
accessible memory medium, comprising program instructions
executable by a processing element to cause a network slice
selection function (NSSF) of a cellular network to: receive a first
network slice selection request from a radio access network (RAN)
node of the cellular network, wherein the first network slice
selection request is associated with a first service request
received by the RAN node from a wireless device; and provide a
first network slice selection response, wherein the first network
slice selection response indicates a control plane entry point
address for a first core network slice.
According to some embodiments, the first network slice selection
request comprises, for the first service request, an indication of
one or more of: wireless device identification information; service
type information; application identification information; or a
preferred network slice.
According to some embodiments, the program instructions are further
executable to cause the NSSF to: determine whether valid
subscription information for the wireless device is stored by the
NSSF; and obtain subscription information for the wireless device
from a home subscriber server (HSS) of the cellular network if
valid subscription information for the wireless device is not
stored by the NSSF, wherein the first network slice selection
response indicates the control plane entry point address for the
first core network slice based at least in part on the subscription
information for the wireless device.
According to some embodiments, the program instructions are further
executable to cause the NSSF to: receive a second network slice
selection request from the RAN node of the cellular network,
wherein the second network slice selection request is associated
with a second service request received by the RAN node from the
wireless device; and provide a second network slice selection
response, wherein the second network slice selection response
indicates a control plane entry point address for a second core
network slice.
According to some embodiments, the program instructions are further
executable to cause the NSSF to: select the first core network
slice of the cellular network for the first service request in
response to the first network slice selection request; and select a
first RAN slice of the cellular network for the first service
request in response to the first network slice selection request,
wherein the first network slice selection response further
indicates that the first core network slice and the first RAN slice
are selected for the first service request.
A still further set of embodiments may include a cellular network
entity of a cellular network, comprising: a network interface; and
a processing element communicatively coupled to the network
interface; wherein the network interface and the processing element
are configured to: receive a first service request from a wireless
device; provide a first network slice selection request associated
with the first service request to a network slice selection
function; receive a first network slice selection response
indicating that a first core network slice of the cellular network
is selected in response to the first network slice selection
request, wherein the first network slice selection response further
indicates a control plane entry point address for the first core
network slice; and establish a connection with the first core
network slice using the indicated control plane entry point address
for the first core network slice, wherein the connection with the
first core network slice is associated with the first service
request.
According to some embodiments, the first service request received
from the wireless device comprises an indication of a first
preferred network slice, wherein the first network slice selection
request comprises an indication of the first preferred network
slice.
According to some embodiments, the cellular network entity
comprises a radio access network (RAN) entity of the cellular
network, wherein the network interface and the processing element
are further configured to: broadcast an indication of one or more
network slices of the cellular network supported by the RAN
entity.
According to some embodiments, the cellular network entity
comprises a radio access network (RAN) entity of the cellular
network, wherein the first network slice selection response further
indicates that a first RAN slice of the cellular network is
selected, wherein the network interface and the processing element
are further configured to: provide RAN resources to the wireless
device from a resource pool associated with the first RAN
slice.
According to some embodiments, the network interface and the
processing element are further configured to: receive a second
service request from the wireless device; provide a second network
slice selection request associated with the second service request
to the network slice selection function; receive a second network
slice selection response indicating that a second core network
slice of the cellular network is selected in response to the second
network slice selection request, wherein the second network slice
selection response further indicates a control plane entry point
address for the second core network slice; and establish a
connection with the second core network slice using the indicated
control plane entry point address for the second core network
slice, wherein the connection with the second core network slice is
associated with the second service request.
According to some embodiments, the connection with the first core
network slice and the connection with the second core network slice
are established in an at least partially temporally overlapping
manner.
According to some embodiments, the first core network slice is a
different core network slice than the second core network
slice.
Another exemplary set of embodiments may include a method
comprising performing any or all parts of any of the preceding
examples.
Still another exemplary set of embodiments may include a computer
program comprising instructions for performing any or all parts of
any of the preceding examples.
Yet another exemplary set of embodiments may include an apparatus
comprising means for performing any or all of the elements of any
of the preceding examples.
Embodiments of the present disclosure may be realized in any of
various forms. For example some embodiments may be realized as a
computer-implemented method, a computer-readable memory medium, or
a computer system. Other embodiments may be realized using one or
more custom-designed hardware devices such as ASICs. Still other
embodiments may be realized using one or more programmable hardware
elements such as FPGAs.
In some embodiments, a non-transitory computer-readable memory
medium may be configured so that it stores program instructions
and/or data, where the program instructions, if executed by a
computer system, cause the computer system to perform a method,
e.g., any of a method embodiments described herein, or, any
combination of the method embodiments described herein, or, any
subset of any of the method embodiments described herein, or, any
combination of such subsets.
In some embodiments, a device (e.g., a network element 500) may be
configured to include a processor (or a set of processors) and a
memory medium, where the memory medium stores program instructions,
where the processor is configured to read and execute the program
instructions from the memory medium, where the program instructions
are executable to implement any of the various method embodiments
described herein (or, any combination of the method embodiments
described herein, or, any subset of any of the method embodiments
described herein, or, any combination of such subsets). The device
may be realized in any of various forms.
It is well understood that the use of personally identifiable
information should follow privacy policies and practices that are
generally recognized as meeting or exceeding industry or
governmental requirements for maintaining the privacy of users. In
particular, personally identifiable information data should be
managed and handled so as to minimize risks of unintentional or
unauthorized access or use, and the nature of authorized use should
be clearly indicated to users.
Although the embodiments above have been described in considerable
detail, numerous variations and modifications will become apparent
to those skilled in the art once the above disclosure is fully
appreciated. It is intended that the following claims be
interpreted to embrace all such variations and modifications.
* * * * *